Eriksen, who was set to leave Spurs on a free transfer at the end of the season, reportedly agreed to sign a four-and-a-half-year contract with Antonio Conte's side.
The 27-year-old said last summer he wanted to "try something new," sparking links with Manchester United and Barcelona. United tracked Eriksen for a brief time but abandoned their pursuit in August.
Tottenham fans booed Eriksen when he was substituted against Liverpool on Jan. 11. Wednesday's 1-0 win over Norwich is expected to mark his final appearance for the club.
Jose Mourinho had urged Eriksen in December to follow Toby Alderweireld's lead and stay in north London. Like Eriksen, Alderweireld entered the 2019-20 campaign on the final year of his contract, and it had looked like the Belgian defender would test the free market before Mauricio Pochettino's firing. Mourinho managed to convince Alderweireld to sign a new contract until June 2023.
But Inter were hellbent on getting a deal done. After opening negotiations with a bid of €10 million, the Nerazzurri reportedly met Spurs' demands and upped the fee.
Barring any last-minute hitches, Eriksen will become Inter's third signing of the winter transfer window, joining former Premier League players Ashley Young and Victor Moses at the Stadio Giuseppe Meazza.